来自MSN1 个月
If The Visible Universe Is 13.7 Billion Years Old, How Is It 93 Billion Light-Years Across?
For Betelgeuse, that actually happened 554 years ago. Things get more complicated when we consider galactic distances. The expansion of the universe is happening everywhere but it is only on vast ...
Forbes1 年
The Most Distant Stars In Our Galaxy Are Halfway To Andromeda, Say Scientists
They allow astronomers to accurately measure galactic distances solely by their brightness. RR Lyrae are old stars with very specific physical properties that cause them to expand and contract in ...